This is norttest2. All its profile fields are set to 23, it uses yellow emotes, scholar ranks, Verdana font override, and has Harvard's logo with the building on the Khmer Rouge flag in the middle as its avatar. (I just used whatever I had lying around...)
Now, when I switch the usernames of these two accounts...
I just tried to create a new account with the username norttest3. Same password as I used for norttest2 (which changed its username to norttest3) so I guess I just got logged in? Huh. If the email address I used for this account contains the string "mkii", it overwrote that.
I just tried to create an account named norttest3 with a different password. No error message, but couldn't log in — dunno if that differs from what happens when you try to register a new user with a username that collides with an account that hasn't changed its username.
I wonder what will happen when I log back in to norttest1 and change its username...? Will it turn registered?
I registered two accounts, norttest1 and norttest2. I gave norttest1 the red face avatar and norttest2 the Harvard avatar.
I changed norttest2's username to norttest3, after which it lost its avatar.
I changed norttest1's username to norttest2, after which it gained norttest2's avatar in place of its own. So avatars are associated with usernames.
I registered a new account (this one) and gave it the username norttest1. I got the "norttest1 messages dialog" menu and could edit my posts, but couldn't update my profile — when I tried to, it complained of username overlap. (There was no other account called norttest1 at this time.) Also, there was no avatar box — not even the default gray box avatar.
I tried to change the username of then-norttest2 (originally norttest1) back to norttest1, which was occupied by the sort-of-account mentioned above. The change didn't go through, but didn't give an error message.
I tried to register a new account called norttest3. That didn't work. That part is described in detail above.
I changed the username of the sort-of-account norttest1 (not the original norttest1, which at that time was called norttest2) to norttest4, at which point it became a full-fledged account, with the gray box avatar and the ability to make a profile and so on. (I don't think I tested blog post creation on the sort-of-account.) Then I changed its username back to norttest1, which worked perfectly.